Title page for ETD etd-08032007-142143

An experimental investigation of heat transfer in three-dimensional and separating turbulent boundary layers

Degree

PhD

Department

Aerospace Engineering

Advisory Committee

Advisor Name

Title

No Advisors Found

Keywords

convection

heat transfer

separration

Date of Defense

1996-04-05

Availability

restricted

Abstract

The turbulence structure of convective heat transfer was studied experimentally
in complex three-dimensional and separating turbulent boundary layers. Three test cases
whose fluid dynamics have been well documented were examined. In case 1, time- and
spatially-resolved surface heat transfer was measured in the nose region of a wing-body
junction formed by a wing and a flat plate. Both the wing and the endwall were heated
and held at a constant uniform temperature 20 °C above ambient temperature. Heat flux
rates were increased up to a factor of 3 over the heat flux rates in the approach boundary
layer. The rms of the heat flux fluctuations were as high as 25% of the mean heat flux
in the vortex-dominated nose region. Away from the wing, upstream of the time-averaged
vortex center, augmentation in the heat flux is due to increased turbulent mixing caused
by large-scale unsteadiness of the vortex. Adjacent to the wing the augmentation in heat
flux is due to a change in the mean velocity field.